Kevin Myatt is The Roanoke Times' weather columnist.

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The West Coast seems to have all kinds of disasters that we rarely think about in the East. Wildfires. Earthquakes. Volcanoes. Landslides.

One thing the West Coast doesn't have, though, is hurricanes.

The reason is simple. The primary ocean currents off the West Coast come from the north, bringing cold water down from Alaska. Any tropical systems that move northward from the Mexican coast lose energy as they move into colder and colder water.

Once in a great while, a tropical storm can make it close to San Diego, but none on record has made it farther north.

Contrast that to the Eastern Seaboard, where a strong current called the Gulf Stream brings a steady flow of warm water northward not far offshore. Hurricanes can hit Newfoundland, and frequently do.

But this past week, the Pacific Northwest experienced a storm that caused more destruction, death and hardship than many hurricanes have.

At least eight people have died in Washington and Oregon from the storm, with damage expected to reach the billions of dollars from flooding and high winds. Washington's governor said the tree damage was like nothing else he had seen since Mount St. Helens erupted in 1980.

The same storm brought less rain than expected to Southern California on Friday but is forecast to bring a swath of rain and snow to the nation's midsection over the weekend and early next week.

A strong northern Pacific low pressure system can be a fearsome beast.

While never as intense as the worst hurricanes, the storms can have winds equal to many weak to moderate hurricanes, and those winds can cover a much greater area.

These storms get their strength not from the latent heat in warm ocean water, as hurricanes do, but from clashing air masses and strong winds high in the atmosphere.

Late fall and early winter in the northern Pacific is a prime time to see storms like this develop, as the jet stream dips farther and farther southward after its summer retreat into the high northern latitudes.

That allows cold air from the North Pole to sink farther south and collide with warm, moist subtropical air from the central Pacific. The large area of open water keeps land features from being a factor, so the storms grow large and powerful.

The Pacific Northwest typically experiences one or two pretty large storms of this nature each year, but this last one was particularly severe, owing some of its strength to two typhoons (the East Asian word for hurricanes) whose remnants were pulled into the developing system. Thousands of people remained without power on Friday.

One thing about Pacific Northwest storms, though, is that it is rare that we catch the brunt of what remains of them as they cross the country. Usually, storms crashing into the West Coast that far north pull in mild, Pacific air across much of the nation, and the storm track is usually such that the low-pressure system passes well north of us.

That will happen again in the upcoming several days. After this week's first bouts with snow and ice, mild air will return and most of the storminess will miss us to the north and west.